Neptune Has 14 Moons: Neptunian Satellite Facts (Infographic) Fourteen moons orbit Neptune, including enigmatic Triton, which moves backward in its orbit. Credit: by Karl Tate, Infographics Artist Of the 14 satellites of Neptune, the largest is Triton, which is in a retrograde (backward) orbit around the planet. Triton is the largest moon in the solar system to do this. On July 15, a 14th moon of Neptune , provisionally called S/2004 N 1, was announced. Neptune has seven inner moons. Their orbits lie among several faint rings and partial rings composed of dust and ice particles. Outwards from Neptune, the inner moons are Naiad, Thalassa, Despina, Galatea, Larissa, S/2004 N 1 and Proteus. Next outward from Neptune , Triton is one of four moons in the solar system known to have an atmosphere. The thin nitrogen haze is thought to have evaporated off of the frozen surface. Triton is Neptune's largest moon , at 1,677 miles (2,700 km) in diameter.

Because Triton moves backward in its orbit, astronomers think the icy moon formed in the frozen Kuiper belt, located in the outer solar system. Later, Neptune's gravity captured Triton. Neptune Quiz: How Well Do You Know the Other Blue Planet? After Triton comes Nereid. At 211 miles (340 km) in diameter, Nereid is one of the largest irregular moons in the solar system . Irregular moons have orbits that are highly inclined to the planet's equator. Much further out than Nereid orbit five outer moons, Halimede, Sao, Laomedeia, Neso and Psmathe. These irregular moons travel in highly tilted orbits. Space Today Online - Moons of the Solar System SPACE TODAY ONLINE ~~ COVERING SPACE FROM EARTH TO THE EDGE OF THE UNIVERSE Moons of the Solar System Massive planet Jupiter below the moon Io click NASA image to enlarge A moon is a natural satellite rotating around a planet. While moons vary in size, each moon is much smaller than its planet. Almost 140 moons are known in the Solar System. Several moons are larger than the planet Pluto and two moons are larger than the planet Mercury.

There also are many small moons that may be asteroids captured by their planets. Only Mercury and Venus do not have any moons. By comparison, Earth has one moon and Mars has two. Jupiter has the most of any planet. Saturn is second. Pictures taken by the Hubble Space Telescope suggest there may be even more moons around those outer planets. earth's moon » Largest. The largest moon is Ganymede with a diameter of 3,280 miles, even larger than either of the planets Mercury and Pluto. Saturn's moon Titan is the second largest in the Solar System with a diameter of 3,200 miles, half again as large as Earth's Moon.

The Planets and Their Moons PLANET Jupiter 62 Io, Europa, Ganymede, Callisto, Amalthea, Himalia, Elara, Pasiphae, Sinope, Lysithea, Carme, Ananke, Leda, Metis, Adrastea, Thebe, Callirrhoe, Themisto, Kalyke, Iocaste, Erinome, Harpalyke, Isonoe, Praxidike, Megaclite, Taygete, Chaldene, Autonoe, Thyone, Hermippe, Eurydome, Sponde, Pasithee, Euanthe, Kale, Orthosie, Euporie, Aitne, plus others yet to receive names Saturn 33 Titan, Rhea, Iapetus, Dione, Tethys, Enceladus, Mimas, Hyperion, Prometheus, Pandora, Phoebe, Janus, Epimetheus, Helene, Telesto, Calypso, Atlas, Pan, Ymir, Paaliaq, Siarnaq, Tarvos, Kiviuq, Ijiraq, Thrym, Skadi, Mundilfari,

 Erriapo, Albiorix, Suttung, plus others yet to receive names Uranus 27 Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Belinda, Puck, Miranda, Ariel, Umbriel, Titania, Oberon, Caliban, Sycorax, Prospero, Setebos, Stephano, Trinculo, plus others yet to receive names Neptune Triton, Nereid, Naiad, Thalassa, Despina, Galatea, Larissa, Proteus, plus others yet to receive names Pluto 139 Saturn.

When the Cassini spacecraft from Earth arrived at Saturn in 2004, it promptly found two previously unseen moons. They turned out to be the smallest bodies seen until then around the ringed planet. The tiny natural satellites are about 2 miles and 2.5 miles in diameter. That's smaller than the city of Boulder, Colorado. Previously, the smallest moons seen around Saturn were are about 12 miles across. The moons are 120,000 miles and 131,000 miles from the center of planet Saturn between the moons Mimas and Enceladus. The newly discovered bodies were labeled S/2004 S1 and S/2004 S2. Later, they will be given names. The NASA JPL team wondered if S/2004 S1 might not be an object called S/1981 S14 that had turned up in a 1981 Voyager image. Saturn moons » Smallest.

The smallest moon is Deimos, at Mars, only seven miles in diameter, although its size now is rivaled by the small shepherd moons discovered by Cassini at Saturn and by others yet to be counted and named in the rings around Jupiter, Saturn and other giant gas planets in the outer Solar System. There may be tiny moons as small as only around a mile across. Pluto. Charon is the moon closest in size to its planet, Pluto. Earth's Moon is second in that comparison. Neptune. The interplanetary probe Voyager 2 in 1989 found six previously-unknown moons orbiting Neptune. They ranged in diameter from 33 miles to 250 miles. In 1991, they were named Naiad, Thalassa, Despina, Galatea, Larissa, Proteus. The names Galatea and Larissa were controversial since asteroids previously had been given those names. Names are assigned by the nomenclature committee of the International Astronomical Union (IAU). Triton. Before Voyager 2, astronomers knew Neptune had two moons, Triton and Nereid.

With a surface temperature of –391 degrees, Triton was found by Voyager 2 to have a thin veneer of methane and nitrogen on top of water ice on its surface. Triton had been thought to have a diameter of 2,361 miles, close in size to Earth's Moon, but turned out to be smaller, around 1,690 miles. Nereid is 210 miles in diameter. Pan. A new moon only 12 miles in diameter was discovered in 1990 circling the planet Saturn. It was Saturn's 18th and most distant moon. Photos of the planet, moons and rings, left over from the 1981 Saturn flyby by Voyager 2, had been filed away at NASA's Ames Research Center in Mountain View, California, for a decade. A planetary scientist was tipped off to Pan's presence by a disturbance in a 200-mi.-wide gap — Encke's Gap — in Saturn's outermost A ring. Pan's gravity moved particles in the large A ring, creating a gap with waves along the edges like the wake of a motorboat.

Checking the wavy edges, he calculated the probable position and mass of the moon and compared them with Voyager 2 positions and camera angles in 1980-81. When finally uncovered, the moon stood out as a small bright spot in 11 pictures among 30,000 photos scanned by a computer. In 1991, the moon officially was named Pan. It was the second time since Neptune was discovered in 1894 that a gravity disturbance had been used to pinpoint a previously-unknown Solar System body. Inner Solar System. The inner Solar System includes the planets Mercury, Venus, Earth and Mars. Of all the known moons in our Solar System, only three are in the inner region. Mars has two. Earth has one. Mercury and Venus are the only planets without moons. The outer Solar System includes Jupiter, Saturn, Uranus, Neptune and Pluto and the rest of the moons. More moons are discovered each year in the outer Solar System by astronomers using ever more powerful equipment. Atmospheres. Most moons are airless, but Jupiter's Io, Saturn's Titan and Neptune's Triton seem to have atmospheres. Titan may be flooded with an ocean of liquid ethane.

Triton may be covered by an ocean of liquid nitrogen. Io seems to have a thin sulphur dioxide atmosphere from volcanos. Titan. Titan appears to have an organic chemistry in its atmosphere which may resemble the primitive Earth before the dawn of life. It is the only moon known to have a thick, organic-rich nitrogen atmosphere. Surface temperature is around –290 degrees Fahrenheit. Solar System's moons are listed below: Exploring the Moons of the Outer Solar System The moons of the outer planets are popular targets with planners of future spaceflights. Jupiter has more moons than any other planet. Its best known moons are the four large planet-sized bodies Io, Europa, Ganymede and Callisto. jupiter » Callisto is the outermost of the four and the most heavily cratered body in the Solar System. It may have a vast water ocean indside. Io is innermost of the four. This sulfurous moon is the most volcanic world in our Solar System. It is peppered with hundreds of volcanoes, several of which might be active at any given moment. Europa has an icy surface that may hide a layer of warm slush or even liquid water.

That would make it one of the few places in the Solar System with that life-sustaining liquid. Ganymede is the largest moon of Jupiter and the largest moon in the Solar System. In fact, Ganymede is larger in diameter than the planet Mercury and much larger than the planet Pluto. Ganymede has its own magnetic field. Saturn has some unique moons. Here are some examples: Titan is Saturn's largest moon. Mimas has an enormous crater – probably a hole caused by a meteorite. Enceladus has a very bright surface. It may have active water volcanoes. Tethys has a canyon running three-quarters of the way around its surface. That means it may once have been split almost in half. Dione and Rhea have wispy white markings on one side. Hyperion is oddly shaped and the length of its day is constantly changing. Iapetus is half bright and half dark. Pan, by comparison, is a very tiny moon. Its diameter is only 20 km, which on the sale above would be only half the size of a BB. Uranus' moons are eye-openers. They have statuesque mountains towering more than ten miles high. Incredibly deep valleys.

Vast plains, some with a mysterious dark surface. Moon diameters range from a bit fatter than 25 miles up to about 1,100 miles. Neptune - Neptune's moons and rings | planet | Britannica.com Earth Of Voyager’s six discoveries, all but Proteus orbit Neptune in less time than it takes the planet to rotate. Hence, to an observer positioned near Neptune’s cloud tops, these five would appear to rise in the west and set in the east. Voyager observed two of its discoveries, Proteus and Larissa, closely enough to detect both their size and approximate shape. Both bodies are irregular in shape and appear to have heavily cratered surfaces. The sizes of the other four are estimated from a combination of distant images and their brightnesses, based on the assumption that they reflect about as much light as Proteus and Larissa—about 7 percent. Proteus, with a mean radius of about 208 km (129 miles), is a little larger than Nereid , with a mean radius of about 170 km (106 miles).

Because Proteus is so near to Neptune, however, scientists on Earth had been unable to detect it in the planet’s glare. The other five moons are much smaller, each having a mean radius of less than 100 km (60 miles). Voyager did not observe Nereid at close range, but data from the probe indicate that it has a nearly spherical shape. Voyager detected no large variations in brightness as Nereid rotated. Although the spacecraft was unable to determine a rotation period, the moon’s highly elliptical orbit makes it unlikely that it is in synchronous rotation—i.e., that its rotation and orbital periods are equal. The rotation period of Triton is synchronous, and those of Neptune’s other inner moons are probably synchronous or very nearly so. Planets: Fact or Fiction? Triton is similar in size, density, and surface composition to the dwarf planet Pluto . Its highly inclined, retrograde orbit suggests that it is a captured object, which perhaps formed originally, like Pluto, as an independent icy planetesimal in the outer solar system.

Its original orbit would have been highly eccentric, but tidal interactions between Triton and Neptune—cyclic deformations in each body caused by the gravitational attraction of the other—eventually would have reshaped its path around Neptune into a circle. The process of Triton’s capture and circularization of its orbit would have severely disrupted any previously existing system of moons that had formed along with Neptune from a disk of protoplanetary material. Nereid’s radical orbit may be one consequence of this process (although the possibility that Nereid too is a captured object has not been ruled out). Moons that were in orbit between Proteus and Nereid would have been ejected from the Neptunian system, thrown into Neptune itself, or absorbed by the molten Triton. Even those moons orbiting closer to Neptune would not have escaped some disruption. The present orbits of Naiad through Proteus are probably very different from their original orbits, and these moons may be only fragments of the original bodies that formed with Neptune. Subsequent bombardment by Neptune-orbiting debris and by meteoroids from interplanetary space may have further altered their sizes, shapes, and orbits. The ring system Ringling Bros.

Folds Its Tent Evidence that Neptune has one or more rings arose in the mid-1980s when stellar occultation studies from Earth occasionally showed a brief dip in the star’s brightness just before or after the planet passed in front of it. Because dips were seen only in some studies and never symmetrically on both sides of the planet, scientists concluded that any rings present do not completely encircle Neptune but instead have the form of partial rings, or ring arcs. Neptune’s ring system, captured by Voyager 2 in two long-exposure backlit images made a few hours … Jet Propulsion Laboratory/National Aeronautics and Space Administration Images from Voyager 2, however, revealed a system of six rings, each of which in fact fully surrounds Neptune. The putative arcs turned out to be bright regions in the outermost ring, named Adams, where the density of ring particles is particularly high. Although rings also encircle each of the other three giant planets, none displays the striking clumpiness of Adams. The arcs are found within a 45° segment of the ring. From leading to trailing, the most prominent are named Courage, Liberté, Egalité 1, Egalité 2, and Fraternité.

They range in length from about 1,000 km (600 miles) to more than 10,000 km (6,000 miles). Although the moon Galatea, which orbits just planetward of the inner edge of Adams, may gravitationally interact with the ring to trap ring particles temporarily in such arclike regions, collisions between ring particles should eventually spread the constituent material relatively uniformly around the ring. Consequently, it is suspected that the event that supplied the material for Adams’s enigmatic arcs—perhaps the breakup of a small moon—occurred within the past few thousand years. Connect with Britannica Facebook Twitter YouTube Instagram Pinterest The other five known rings of Neptune— Galle, Le Verrier, Lassell, Arago, and Galatea, in order of increasing distance from the planet—lack the nonuniformity in density exhibited by Adams. Le Verrier, which is about 110 km (70 miles) in radial width, closely resembles the nonarc regions of Adams. Similar to the relationship between the moon Galatea and the ring Adams, the moon Despina orbits Neptune just planetward of the ring Le Verrier.

Each moon may gravitationally repel particles near the inner edge of its respective ring, acting as a shepherd moon to keep ring material from spreading inward. (For fuller treatments of shepherding effects, see Saturn: Moons: Orbital and rotational dynamics ; Uranus: The ring system .) Galle, the innermost ring, is much broader and fainter than either Adams or Le Verrier, possibly owing to the absence of a nearby moon that could provide a strong shepherding effect. Lassell consists of a faint plateau of ring material that extends outward from Le Verrier about halfway to Adams. Arago is the name used to distinguish a narrow, relatively bright region at the outer edge of Lassell. Galatea is the name generally used to refer to a faint ring of material spread all along the orbit of the moon Galatea. Rings of Neptune Solar System Header Naiad was the last moon to be discovered during the Voyager 2 flyby in September 1989. How Naiad Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans.

Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Naiad (Nye-ed) is named after a type of nymph who presided over fountains, wells, springs, streams, and brooks in Greek mythology. Naiad was originally designated S/1989 N 6. Thalassa Grainy black and white image showing three moons at Neptune. A Voyager 2 image of Thalassa (1989 N5), Naiad (1989 N5) and Despina (1989 N3) taken in 1989 at a range of 5.9 million kilometers (3.6 million miles). A Voyager 2 image of Thalassa (1989 N5), Naiad (1989 N5) and Despina (1989 N3) taken in 1989 at a range of 5.9 million kilometers (3.6 million miles). Thalassa, like Naiad, most likely formed from fragments of Neptune's original moons, which were smashed by the disturbances caused when the ice giant Neptune captured Triton.

Thalassa is unusual for an irregular moon because it is roughly disk-shaped. Also like Naiad, Thalassa circles the planet in the same direction as Neptune rotates, and remains close to Neptune's equatorial plane. Thalassa's orbit is slowly decaying due to tidal deceleration and may eventually crash into Neptune's atmosphere or be torn apart and form a planetary ring. Despina Despina is a tiny moon located within Neptune's faint ring system. The irregularly-shaped moon orbits Neptune every eight hours, circling in the same direction as Neptune's own rotation. Despina remains close to Neptune's equatorial plane. Discovery: Despina was discovered in July 1989 by the Voyager 2 science team. How Despina Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Despina is a daughter of Poseidon (the Roman god Neptune) and Demeter.

Despina was originally designated S/1989 N3 Galatea Galatea was discovered in July 1989 by the Voyager 2 science team. Galatea is another of Neptune's tiny moons. Small and irregularly-shaped like Despina, Galatea orbits in the same direction as Neptune and is relatively close to the gas giant's equatorial plane. The small moon's gravity is believed to cause disturbances in Neptune's ring system. It was found in the same month scientists discovered ring arcs, or partial rings, that were suspected to exist around Neptune. Galatea circles Neptune every 10 hours and 18 minutes. Discovery: How Galatea Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Galatea was a sea nymph who attended to Poseidon (the Roman god Neptune). The nymphs are also known as the Nereids. The moon was originally designated S/1989 N 4.

Larissa Two views of dark, irregularly-shaped Larissa captured by Voyager 2. Discovery: Although it was initially spotted by H. Reitsema, W. Hubbard, L. Lebofsky, D. Tholen through the use of ground-based telescopes in 1981. Larissa was officially discovered in July 1989 by the Voyager 2 science team. How Larissa Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Larissa was a nymph from Greek mythology. The moon was originally designated S/1989 N 2. Proteus Fuzzy image of the moon Proteus. Fuzzy image of the moon Proteus. Proteus' irregular shape suggests it has been cold and rigid throughout its history and subject to significant impact cratering. Proteus is one of the largest of Neptune's known moons, although it is not as big as Triton.

The moon has an odd box-like shape and if it had just a little more mass it would be able to transform into a sphere. Proteus orbits Neptune about every 27 hours. Proteus is irregularly shaped and heavily cratered, but it shows no sign of geological modification. Circling the planet in the same direction as Neptune rotates, Proteus remains close to Neptune's equatorial plane. Proteus is one of the darkest objects in our solar system. Like Saturn's moon Phoebe, Proteus reflects only 6 percent of the sunlight that hits it. Discovery: Proteus was discovered in 1989 by the Voyager 2 spacecraft. This is unusual since a smaller moon, Nereid, was discovered 33 years earlier using an Earth-based telescope. Proteus was most likely overlooked because it is so dark and the distance between Earth and Neptune is so great. How Proteus Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune.

Proteus is named after the shape-changing sea god of Greek mythology. Proteus was originally designated S/1989 N 1 Halimede Scientists used this faint, fuzzy image to pinpoint one of three new Neptunian moons more than 4 billion km (2.8 billion miles) from the Sun. This is Halimede (S/2002 N1). Halimede is one of three tiny moons (ranging in size from 30 to 40 km -- or 18 to 24 miles) of Neptune discovered in 2002 using innovative ground-based telescope techniques. (The other moons discovered were Laomedeia and Sao.) The moons are so distant and so small they are about 100 million times fainter than can be seen with the unaided eye. The moons were missed by the Voyager 2 spacecraft in 1989 because they are so faint and distant from Neptune. Halimede is considered an irregular satellite because of its distant, eccentric orbit around Neptune. Like most irregular satellites of the giant planets in our outer solar system, Halimede most likely formed after a collision between a larger moon and a comet or an asteroid.

Sao and Laomedeia have prograde orbits, which means they orbit in the same direction as Neptune's rotation. Halimede has a retrograde orbit, which means Halimede orbits in the opposite direction of Neptune's rotation. Discovery: Very little is known about Halimede. Scientists are trying to learn more about it and its irregular sisters because they offer a glimpse of the conditions at the time the planets in our solar system were forming billions of years ago. Halimede was discovered 14 August 2002 by Matthew J. Holman, John J. Kavelaars, Tommy Grav, Wesley C. Fraser, and Dan Milisavljevic using images taken by the 4.0-m Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile and the 3.6-m Canada-France-Hawaii Telescope in Hawaii. Multiple images were digitally combined until stars appeared as streaks, while the moons appeared as points of light.

Halimede, Laomedeia and Sao were discovered through the use of Earth-based telescopes -- this was the first time a Neptunian moon discovery had occurred by telescope since the discovery of Nereid in 1949 by Gerard Kuiper. How Halimede Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Halimede is named after one of the Nereids. Halimede was originally designated S/2002 N 1. Psamathe Psamathe is so distant from Neptune< it takes almost 26 Earth years to make a single orbit around the ice giant. The moon's orbit is among the most distant from its planet than any other known moon in our solar system. The small moon shares similar orbital parameters with with another moon of Neptune -- Neso. Both Psamathe and Neso may be fragments from the break-up of a larger moon billions of years ago. Discovery: Psamathe was discovered by Scott S. Sheppard, David C.

Jewitt and Jan T. Kleyna 29 August 2003 using the 8.3-m Subaru reflector at the Mauna Kea Observatory on the island of Hawaii. How Psamathe Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Psamathe like many of the satellites of Neptune, is named after one of the Nereids. Psamathe was originally designated S/2003 N 1. Sao Sao is one of three tiny moons (ranging in size from 30 to 40 km -- or 18 to 24 miles) of Neptune discovered in 2002 using innovative ground-based telescope techniques. (The other moons discovered were Laomedeia and Halimede.) The moons are so distant and so small they are about 100 million times fainter than can be seen with the unaided eye.

The moons were missed by the Voyager 2 spacecraft in 1989 because they are so faint and distant from Neptune. Sao is considered an irregular satellite because of its distant, eccentric orbit around Neptune. Like most irregular satellites of the giant planets in our outer solar system, Sao most likely formed after a collision between a larger moon and a comet or an asteroid. Sao and Laomedeia have prograde orbits, which means they orbit in the same direction as Neptune's rotation. Halimede has a retrograde orbit, which means Halimede orbits in the opposite direction of Neptune's rotation. Very little is known about Sao. Scientists are trying to learn more about it and its irregular sisters because they offer a glimpse of the conditions at the time the planets in our solar system were forming billions of years ago. Discovery: Sao was discovered 14 August 2002 by Tommy Grav, Matthew J. Holman, John J. Kavelaars, Wesley C. Fraser, and Dan Milisavljevic using images taken by the 4.0-m Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile and the 3.6-m Canada-France-Hawaii Telescope in Hawaii.

Multiple images were digitally combined until stars appeared as streaks, while the moons appeared as points of light. Sao, Laomedeia and Halimede were discovered through the use of Earth-based telescopes -- this was the first time a Neptunian moon discovery had occurred by telescope since the discovery of Nereid in 1949 by Gerard Kuiper. How Sao Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Sao is named for one of the Nereids. Sao was originally designated as S/2002 N 2. Laomedeia Laomedeia is one of three tiny moons (ranging in size from 30 to 40 km -- or 18 to 24 miles) of Neptune discovered in 2002 using innovative ground-based telescope techniques.

(The other moons discovered were Sao and Halimede.) The moons are so distant and so small they are about 100 million times fainter than can be seen with the unaided eye. The moons were missed by the Voyager 2 spacecraft in 1989 because they are so faint and distant from Neptune. Laomedeia is considered an irregular satellite because of its distant, eccentric orbit around Neptune. Like most irregular satellites of the giant planets in our outer solar system, Laomedeia most likely formed after a collision between a larger moon and a comet or an asteroid. Laomedeia and Sao have prograde orbits, which means they orbit in the same direction as Neptune's rotation. Halimede has a retrograde orbit, which means Halimede orbits in the opposite direction of Neptune's rotation. Very little is known about Laomedeia. Scientists are trying to learn more about it and its irregular sisters because they offer a glimpse of the conditions at the time the planets in our solar system were forming billions of years ago. Discovery: Laomedeia was discovered 13 August 2002 by Matthew J. Holman, John J. Kavelaars, Tommy Grav, Wesley C.

Fraser, and Dan Milisavljevic using images taken by the 4.0-m Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile and the 3.6-m Canada-France-Hawaii Telescope in Hawaii. Multiple images were digitally combined until stars appeared as streaks, while the moons appeared as points of light. Laomedeia, Sao and Halimede were discovered through the use of Earth-based telescopes -- this was the first time a Neptunian moon discovery had occurred by telescope since the discovery of Nereid in 1949 by Gerard Kuiper. How Laomedeia Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Laomedeia is named for one of the Nereids. Laomedeia was originally designated as S/2002 N 3. Neso Very little is known about Neso, another of Neptune's extremely distant irregular moons. Neso's eccentric orbit takes it millions of kilometers from the ice giant.

The moon's orbit is among the most distant from its planet than any other known moon in our solar system. The small moon shares similar orbital parameters with another moon of Neptune -- Psamathe. Both Neso and Psamathe may be fragments from the break-up of a larger moon billions of years ago. Discovery: Neso was discovered in 2002 by Matthew J. Holman, John J. Kavelaars, Tommy Grav, Wesley C. Fraser, and Dan Milisavljevic using the 4-m Blanco telescope at Cerro Tololo Observatory in Chile. How Neso Got its Name: Moons of Neptune are named for characters from Greek or Roman mythology associated with Neptune or Poseidon, or the oceans. Irregular satellites are named for the Nereids, daughters of Nereus and Doris and the attendants of Neptune. Neso like many of the outer satellites of Neptune, is named after one of the Nereids. Neso was originally designated S/2002 N 4. Planet Neptune: Facts About Its Orbit, Moons & Rings Planet Neptune: Facts About Its Orbit, Moons & Rings By Charles Q.

Choi, Space.com Contributor | November 25, 2014 05:14pm ET MORE Neptune’s winds travel at more than 1,500 mph, and are the fastest planetary winds in the solar system. Credit: NASA/JPL Neptune is the eighth planet from the sun. It was the first planet to get its existence predicted by mathematical calculations before it was actually seen through a telescope on Sept. 23, 1846. Irregularities in the orbit of Uranus led French astronomer Alexis Bouvard to suggest that the gravitational pull from another celestial body might be responsible. German astronomer Johann Galle then relied on subsequent calculations to help spot Neptune via telescope . Previously, astronomer Galileo Galilei sketched the planet, but he mistook it for a star due to its slow motion. In accordance with all the other planets seen in the sky, this new world was given a name from Greek and Roman mythology — Neptune, the Roman god of the sea. Physical characteristics Neptune's cloud cover has an especially vivid blue tint that is partly due to an as-yet-unidentified compound and the result of the absorption of red light by methane in the planets mostly hydrogen-helium atmosphere.

Photos of Neptune reveal a blue planet, and it is often dubbed an ice giant, since it possesses a thick, slushy fluid mix of water, ammonia and methane ices under its atmosphere and is roughly 17 times Earth's mass and nearly 58 times its volume, according to a NASA fact sheet . Neptune's rocky core alone is thought to be roughly equal to Earth's mass , NASA says. Despite its great distance from the sun , which means it gets little sunlight to help warm and drive its atmosphere, Neptune's winds can reach up to 1,500 mph (2,400 kph), the fastest detected yet in the solar system . These winds were linked with a large dark storm that Voyager 2 tracked in Neptune's southern hemisphere in 1989. This oval-shaped, counterclockwise-spinning "Great Dark Spot" was large enough to contain the entire Earth, and moved westward at nearly 750 mph (1,200 kph). This storm seemed to have vanished when the Hubble Space Telescope later searched for it. Hubble has also revealed the appearance and then fading of two other Great Dark Spots over the past decade.

Neptune's magnetic poles are tipped over by roughly 47 degrees compared with the poles along which it spins. As such, the planet's magnetic field, which is about 27 times more powerful than Earth's, undergoes wild swings during each rotation. By studying the cloud formations on the gas giant, scientists were able to calculate that a day on Neptune lasts just under 16 hours . Orbital characteristics Neptune's elliptical, oval-shaped orbit keeps the planet an average distance from the sun of almost 2.8 billion miles (4.5 billion kilometers), or roughly 30 times as far away as Earth, making it invisible to the naked eye. Neptune goes around the sun once roughly every 165 Earth years, and completed its first orbit, since being discovered , in 2011. Every 248 years, Pluto moves inside Neptune's orbit for 20 years or so, during which time it is closer to the sun than Neptune. Nevertheless, Neptune remains the farthest planet from the sun, since Pluto was reclassified as a dwarf planet in 2006.

Composition & structure Atmospheric composition (by volume): hydrogen, 80 percent; helium, 19.0 percent; methane, 1.5 percent Magnetic field: Roughly 27 times more powerful than Earth's Composition : The overall composition of Neptune is, by mass, thought to be about 25 percent rock, 60 to 70 percent ice, and 5 to 15 percent hydrogen and helium, according to Tristan Guillot, author of "Interiors of Giant Planets Inside and Outside the Solar System" in the journal Science. Internal structure: Mantle of water, ammonia and methane ices; Core of iron and magnesium-silicate Orbit & rotation Average distance from the sun: 2,795,084,800 miles (4,498,252,900 km). By comparison: 30.069 times farther than Earth Perihelion (closest approach to the sun): 2,771,087,000 miles (4,459,630,000 km).

By comparison: 29.820 times that of Earth Aphelion (farthest distance from the sun): 2,819,080,000 miles (4,536,870,000 km). By comparison: 30.326 times that of Earth (Source: NASA ) Neptune's moons Neptune has 14 known moons , named after lesser sea gods and nymphs from Greek mythology. The largest by far is Triton , whose discovery on Oct. 10, 1846, was in a sense enabled by beer — amateur astronomer William Lassell used the fortune he made as a brewer to finance his telescopes. Triton is the only spherical moon of Neptune — the planet's other 13 moons are irregularly shaped. It is also unique in being the only large moon in the solar system to circle its planet in a direction opposite to its planet's rotation — this " retrograde orbit " suggests that Triton may once have been a dwarf planet that Neptune captured rather than forming in place, according to NASA.

Neptune's gravity is dragging Triton closer to the planet, meaning that millions of years from now, Triton will come close enough for gravitational forces to rip it apart. Triton is extremely cold, with temperatures on its surface reaching about minus 391 degrees F (minus 235 degrees C), making it one of the coldest places in the solar system. Nevertheless, Voyager 2 detected geysers spewing icy matter upward more than 5 miles (8 km), showing its interior appears warm. Scientists are investigating the possibility of a subsurface ocean on the icy moon. In 2010, seasons were discovered on Triton. In 2013, scientists working with SETI caught sight of Neptune's "lost" moon of Naiad using data from the Hubble Space Telescope.The 62-mile-wide (100 km) moon has remained unseen since Voyager 2 discovered it in 1989. Also in 2013, scientists using the Hubble Space Telescope found the 14th moon, dubbed S/2004 N 1. It is Neptune's smallest moon and is just 11 miles (18 km) wide.

It got its temporary name because it is the first satellite (S) of Neptune (N) to be found from images taken in 2004, according to NASA . The rings of Neptune Neptune's unusual rings are not uniform, but possess bright thick clumps of dust called arcs. The rings are thought to be relatively young and short-lived . Earth-based observations announced in 2005 found that Neptune's rings are apparently far more unstable than previously thought, with some dwindling away rapidly, according to an article in the journal Icarus . Research & exploration NASA's Voyager 2 satellite was the first and as yet only spacecraft to visit Neptune on Aug. 25, 1989. The satellite discovered Neptune's rings and six of the planet's moons — Despina, Galatea, Larissa, Naiad, Proteus and Thalassa. An international team of astronomers relying on ground telescopes announced the discovery of five new moons orbiting Neptune in 2003. Formation of Neptune Neptune is generally thought to have formed with the initial buildup of a solid core followed by the capture of surrounding hydrogen and helium gas in the nebula surrounding the early sun.

In this model, proto-Neptune formed over the course of 1 to 10 million years. Additional reporting by Nola Taylor Redd, Space.com Contributor Additional resources Moons - Facts about the Moons of the Solar System Moons Eris Moons There are more than 181 moons of the various planets, dwarf planets and asteroid in the solar system. The planets Mercury and Venus do not have any moons and neither does the dwarf planet Ceres. Find out the number of moons each planet has and their names below. Terrestrial Planet Moons The Earth’s Moon – 1 The Earth has a single moon; the Moon sometime also referred to as Luna. The Moon Mars’ Moons – 2 Mars has two moons called Phobos and Deimos. They were discovered in 1877 by astronomer Asaph Hall, who named them for the Latin terms “fear” and “panic”. These moons are thought to be captured asteroids and are among the smallest natural satellites in the solar system. Phobos & Deimos Jupiter’s Moons – 67 Jupiter is swarming with at least 67 moons in orbit around it, the largest number of natural satellites around any of the planets.

Jupiter’s 4 largest moons; Ganymede, Callisto, Io and Europa are known as the Galilean Moons, named after their discoverer Galileo Galilei. They were also observed at about the same time by astronomer Simon Marius.

Galilean Moons – Io , Europa , Ganymede & Callisto Inner Moons – Metis, Adrastea, Amalthea & Thebe Other Moons – Themisto, Leda, Himalia, Lysithea, Elara, S/2000 J 11, Carpo, S/2003 J 12, Euporie, S/2003 J 3, S/2003 J 18, S/2011 J 1, S/2010 J 2, Thelxinoe, Euanthe, Helike, Orthosie, Iocaste, S/2003 J 16, Praxidike, Harpalyke, Mneme, Hermippe, Thyone, Ananke, Herse, Aitne, Kale, Taygete, S/2003 J 19, Chaldene, S/2003 J 15, S/2003 J 10, S/2003 J 23, Erinome, Aoede, Kallichore, Kalyke,

 Carme, Callirrhoe, Eurydome, S/2011 J 2, Pasithee, S/2010 J 1, Kore, Cyllene, Eukelade, S/2003 J 4, Pasiphae, Hegemone, Arche, Isonoe, S/2003 J 9, S/2003 J 5, Sinope, Sponde, Autonoe, Megaclite & S/2003 J 2 Saturn’s Moons – 62 Saturn has at least 62 moons orbiting it, some of them inside the ring system which helps shape the rings.

They range from very tiny worlds of less than a kilometer in diameter to spherical moons such as Titan. Their shapes range from irregular worlds to ellipsoidal to almost completely rounded. The first of Saturn’s moons to be observed was Titan in 1655 by Christiaan Huygens, another moon was not found until 1671 when Giovanni Domenico Cassini discovered Iapetus. Two of Saturn’s moons (Janus & Epimetheus) swap orbits every 4 years. Notable Moons – Titan , Enceladus , Iapetus , Rhea , Mimas, Tethys & Dione.

Other Moons – S/2009 S 1, Pan, Daphnis, Atlas, Prometheus, Pandora, Epimetheus, Janus, Aegaeon, Methone, Anthe, Pallene, Telesto, Calypso, Helene, Polydeuces, Hyperion, Kiviuq, Ijiraq, Phoebe, Paaliaq, Skathi, Albiorix, S/2007 S 2, Bebhionn, Erriapus, Skoll, Siarnaq, Tarqeq, S/2004 S 13, Greip, Hyrrokkin, Jarnsaxa, Tarvos, Mundilfari, S/2006 S 1, S/2004 S 17, Bergelmir, Narvi, Suttungr, Hati, S/2004 S 12, Farbauti, Thrymr, Aegir, S/2007 S 3, Bestla, S/2004 S 7, S/2006 S 3, Fenrir, Surtur, Kari, Y

mir, Loge & Fornjot Uranus’ Moons – 27 Uranus is known to have 27 in orbit around it.

The five largest are Puck, Miranda, Ariel, Umbriel, Titania, and Oberon. The innermost moons are similar in characteristics with the thin rings. The five largest moons are rounded, and four of them show some kind of internal activity which shapes their surfaces. William Herschel who discovered Uranus in 1781 also observed the largest two moons, Titania and Oberon, in 1787. Notable Moons – Miranda , Titania , Ariel, Umbriel & Oberon Other Moons – Cordelia, Ophelia, Bianca, Cressida, Desdemona, Juliet, Portia, Rosalind, Cupid, Belinda, Perdita, Puck, Mab, Francisco, Caliban, Stephano, Trinculo, Sycorax, Margaret, Prospero, Setebos & Ferdinand Neptune’s Moons – 14 Neptune has at least 14 moons. The largest of these, Triton was discovered by William Lassell in 1846 one day after the discovery of Neptune, it was more than 100 years later before a second moon was found.

The most distant moon of Neptune is called Neso, and orbits so far away that it takes 26 years to make one trip around the planet. Notable Moons – Triton , Nereid & Proteus Other Moons – Naiad, Thalassa, Despina, Galatea, Larissa, S/2004 N 1, Halimede, Sao, Laomedeia, Psamathe & Neso Pluto’s Moons – 5 Hydra, Nyx, Styx, and Kerberos are the smaller moons of Pluto. They lie out beyond Charon. Nix and Hydra were discovered using Hubble Space Telescope on May 15, 2005. They have nearly circular orbits at 48,700 and 64,800 kilometres, respectively. Kerberos was discovered in 2011, and Styx was found in 2012, both by Hubble Space Telescope. These four moons rotate chaotically on their axes. These moons were likely created during a giant collision, which scattered these tiny worlds into orbit around Pluto and Charon.

Question: Despina and Proteus are moons orbiting which planet of the solar system?
Answer: Neptune